This circuit, found in a 1964 US documentation, consists of a selective amplifier that lets only 10 Hz pass around a 400 Hz center frequency with the indicated components.
This amplifier for public address was found in English documentation from 1967. The transistors are from...
January 2017 - Pulse Electronics ER11 transformers with high insulation can be obtained from...
With only 1% distortion, this Motorola amplifier found in a 1968 documentation makes use of period...